At an input station on an endless belt conveyor, as used for transporting coal, ore, sand, gravel or other such materials, spillage of the conveyed material over the edges of the belt may present a substantial problem. Such spillage is usually controlled by a covered chute having fixed walls extending along the edges of the conveyor belt for a substantial distance downstream from the input location. Rigid chute walls engaging the belt edges, however, would create undue friction and cause excessive wear on the belt in addition to overloading the conveyor drive. Consequently, it has been conventional practice to locate the chute walls a short distance above the edges of the conveyor belt and to mount flexible rubber or resin skirtboards, sometimes referred to as skirtboard aprons, on the chute walls to close the resulting gap.
A number of relatively successful arrangements have been provided for mounting flexible, resilient skirtboards on the input chute walls for belt conveyors. Many of these have provided for vertical adjustment of the skirtboards or aprons to compensate for wear on their edges adjacent the moving belt. Thus, skirtboards equipped with vertically adjustable aprons of rubber, resin, canvas, or other resilient materials are described in Roberts U.S. Pat. Nos. 2,593,610 and in Clegg 3,499,523. A substantially improved vertically adjustable skirtboard mounting for use with a conveyor is described in Gordon U.S. Pat. No. 4,231,471. Another effective skirtboard mounting system, particularly notable for its capability of quick release and re-mounting of the skirtboard to avoid any requirement for shutdown of the conveyor system, is disclosed in Gordon U.S. Pat. No. 4,436,446.
Yet another prior conveyor skirtboard mounting arrangement, in which the skirtboard is formed by a multiplicity of individual apron segments, is described in Stahura U.S. Pat. No. 4,236,628. In that arrangement the individual skirtboard sections interfit with each other along their edges, as in a tongue and groove arrangement, so that they can slide vertically relative to each other and still form a substantially continuous skirtboard along the chute wall. This arrangement provides additional flexibility, compared with skirtboard mounts that utilize continuous elongated aprons. The overall construction, however, entails the use of a relatively complex and expensive mounting plate that may not always do an adequate job of holding the skirtboard sections in the desired position immediately adjacent the edges of the conveyor belt.